Abstract

In this study, the authors investigated the rectifying bipolar resistive switching characteristics of Pt/HfO2/TaOx/Pt heterostacks with respect to the chemical bonding states of the TaOx base layer and the physical properties of the insulator layer. The authors demonstrated that the migration of oxygen ions at the interface between the HfO2insulator layer and the TaOx base layer produced the rectifying bipolar resistive switching, and the switching current could be controlled via the oxygen concentration in the TaOx layer. They also observed that the current at the high-resistance state decreased with increasing thickness of the HfO2insulator layer. Rectifying bipolar resistive switching behavior was additionally demonstrated by using an Al2O3 layer as an insulator instead of HfO2.

This work was supported by the “R&D Program of the Ministry of Knowledge Economy,” an industry–university cooperation project of SK Hynix Semiconductor Inc., and the second stage of the Brain Korea 21 Project (BK21).